Clarified Readme for Spidering option

Provided clarification in the readme for how the spider option works.
Explicitly mention commenting out/removing the `path:` section in the
config.yaml file.
Exclude tags from appearing in the spider results

Added a rule for anemone to skip all links that match the regex pattern
specified in the file.  Should exclude any /tags* files from appearing
in the spider.  Those files don’t render properly when scraping w/
wraith and should be excluded from future uses.